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Thiophane
Tetrahydrothiophene is an organosulfur compound with the formula (CH2)4S. The molecule consists of a five-membered saturated ring with four Methylene group, methylene groups and a sulfur atom. It is the Saturated and unsaturated compounds, saturated structural analog, analog of thiophene and is therefore the sulfur analog of Tetrahydrofuran, THF. It is a volatile, colorless liquid with an intensely unpleasant odor. It is also known as thiophane, thiolane, or THT. Synthesis and reactions Tetrahydrothiophene is prepared by the reaction of tetrahydrofuran with hydrogen sulfide. This vapor-phase reaction is catalyzed by alumina and other heterogenous acid catalysts. This compound is a ligand in coordination chemistry, an example being the complex chloro(tetrahydrothiophene)gold(I). Oxidation of THT gives the sulfone sulfolane, which is of interest as a polar, odorless solvent: : Sulfolane is, however, more conventionally prepared from butadiene. Natural occurrence Both unsubstitut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odor
An odor (American English) or odour ( Commonwealth English; see spelling differences) is a smell or a scent caused by one or more volatilized chemical compounds generally found in low concentrations that humans and many animals can perceive via their olfactory system. While ''smell'' can refer to pleasant and unpleasant odors, the terms ''scent'', ''aroma'', and ''fragrance'' are usually reserved for pleasant-smelling odors and are frequently used in the food and cosmetic industry to describe floral scents or to refer to perfumes. Odor physiology Sense of smell The perception of odors, or sense of smell, is mediated by the olfactory nerve. The olfactory receptor (OR) cells are neurons present in the olfactory epithelium, which is a small patch of tissue at the back of the nasal cavity. There are millions of olfactory receptor neurons that act as sensory signaling cells. Each neuron has cilia in direct contact with the air. Odorous molecules bind to receptor pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahydrofuran
Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water- miscible organic liquid with low viscosity. It is mainly used as a precursor to polymers. Being polar and having a wide liquid range, THF is a versatile solvent. It is an isomer of another solvent, butanone. Production About 200,000 tonnes of tetrahydrofuran are produced annually. The most widely used industrial process involves the acid-catalyzed dehydration of 1,4-Butanediol, 1,4-butanediol. Ashland Inc., Ashland/ISP is one of the biggest producers of this chemical route. The method is similar to the production of diethyl ether from ethanol. The butanediol is derived from Condensation reaction, condensation of acetylene with formaldehyde followed by hydrogenation. DuPont developed a process for producing THF by oxidizing Butane#Isomers, ''n''-butane to crude maleic anhydride, follow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloro(tetrahydrothiophene)gold(I)
Chloro(tetrahydrothiophene)gold(I), abbreviated (tht)AuCl, is a coordination complex of gold Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal .... Like the dimethyl sulfide analog, this compound is used as an entry point to gold chemistry. The tetrahydrothiophene ligand is labile and is readily substituted with other stronger ligands. Preparation This compound may be prepared by the reduction of tetrachloroauric acid with tetrahydrothiophene: : The complex adopts a linear coordination geometry, as is typical of many gold(I) compounds. It crystallizes in the orthorhombic space group ''Pmc''21 with a = 6.540(1) Å, b = 8.192(1) Å, c = 12.794(3) Å with Z = 4 formula units per unit cell. The bromide congener is isostructural. It is somewhat less thermally labile compared to (Me2S) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albomycin
Albomycins are a group of naturally occurring antibiotics belonging to the class of sideromycins, which are "compounds composed of iron carriers called siderophores linked to antibiotic moieties". They are particularly effective against Gram-negative bacteria of the family ''Enterobacteriaceae'' and few Gram-positive bacteria such s ''Streptococcus pneumoniae'', ''Bacillus subtilis'' and ''Staphylococcus aureus''. In 2000 a group of scientists from SmithKline Beecham Pharmaceuticals, UK reported that the antibiotic part of albomycin ''in vitro'' can inhibit seryl-tRNA synthetase from both eukaryotic and prokaryotic representatives. Structure Albomycins are naturally occurring sideromycins produced by some streptomycetes. The siderophore part of albomycin δ2 is similar to ferrichrome. It contains three molecules of δ-N-hydroxy-δ-N-acetyl ornithine linked to a serine, all by peptide linkage. The C-terminus of the serine is linked to another serine attached to the antibiotica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedron (journal)
''Tetrahedron'' is a weekly peer-reviewed scientific journal covering the field of organic chemistry. According to the ''Journal Citation Reports'', ''Tetrahedron'' has a 2020 impact factor of 2.1. ''Tetrahedron'' and Elsevier, its publisher, support an annual symposium. In 2010, complaints were raised over its high subscription cost. Notable papers , the Web of Science lists ten papers from ''Tetrahedron'' that have more than 1000 citations. The four articles that have been cited more than 2000 times are: * – cited 2228 times * – cited 2162 times * – cited 2124 times * – cited 2107 times See also * ''Tetrahedron Letters'' * '' Tetrahedron Computer Methodology'' * ''Polyhedron In geometry, a polyhedron (: polyhedra or polyhedrons; ) is a three-dimensional figure with flat polygonal Face (geometry), faces, straight Edge (geometry), edges and sharp corners or Vertex (geometry), vertices. The term "polyhedron" may refer ...'' (journal) Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salacia (plant)
''Salacia'' is a genus of plants in the family Celastraceae. They are woody climbers naturally found in tropical regions. Several species in this genus have been used in traditional medicine, such as the Ayurvedic system from India. The chemical constituents of root bark include polyphenols such as salacinol, kotalanol, and mangiferin. Species , Plants of the World Online accepts the following species: *'' Salacia acevedoi'' *'' Salacia adolphi-friderici'' *'' Salacia agasthiamalana'' *'' Salacia alata'' *'' Salacia alveolata'' *'' Salacia alwynii'' *'' Salacia amplectens'' *'' Salacia amplifolia'' *'' Salacia aneityensis'' *'' Salacia annettae'' *'' Salacia arborea'' *'' Salacia arenicola'' *'' Salacia aurantiaca'' *'' Salacia bangalensis'' *'' Salacia beddomei'' *'' Salacia belingana'' *'' Salacia blepharophora'' *'' Salacia brunoniana'' *'' Salacia bussei'' *'' Salacia caillei'' *'' Salacia callensii'' *'' Salacia caloneura'' *'' Salacia capitulata' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytochemistry Letters
''Phytochemistry'' is a peer-reviewed scientific journal covering pure and applied plant chemistry, plant biochemistry and molecular biology. It is published by Elsevier and is an official publication for the Phytochemical Society of Europe, the Phytochemical Society of North America, and the Phytochemical Society of Asia. A sister journal ''Phytochemistry Letters'' is published since 2008. Abstracting and indexing ''Phytochemistry'' is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 4.072. References External links *{{Official website, http://www.journals.elsevier.com/phytochemistry/ Biochemistry journals Botany journals Elsevier academic journals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allium Schoenoprasum
Chives, scientific name ''Allium schoenoprasum'', is a species of flowering plant in the family Amaryllidaceae. A perennial plant, ''A. schoenoprasum'' is widespread in nature across much of Eurasia and North America. It is the only species of ''Allium'' native to both the New and the Old Worlds. The leaves and flowers are edible. Chives are a commonly used herb and vegetable with a variety of culinary uses. They are also used to repel insects. Description Chives are a bulb-forming herbaceous perennial plant, growing to tall. The bulbs are slender, conical, long and broad, and grow in dense clusters from the roots. The scapes (or stems) are hollow and tubular, up to long and across, with a soft texture, although, prior to the emergence of a flower, they may appear stiffer than usual. The grass-like leaves, which are shorter than the scapes, are also hollow and tubular, or terete (round in cross-section). The flowers are pale purple, and star-shaped with six pet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allium Cepa
An onion (''Allium cepa'' , from Latin ), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus ''Allium''. The shallot is a botanical variety of the onion which was classified as a separate species until 2011. The onion's close relatives include garlic, scallion, leek, and chives. The genus contains several other species variously called onions and cultivated for food, such as the Japanese bunching onion ''Allium fistulosum'', the tree onion ''Allium'' × ''proliferum'', and the Canada onion ''Allium canadense''. The name '' wild onion'' is applied to a number of ''Allium'' species, but ''A. cepa'' is exclusively known from cultivation. Its ancestral wild original form is not known, although escapes from cultivation have become established in some regions. The onion is most frequently a biennial or a perennial plant, but is usually treated as an annual and harvested in its first growing season. The onion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allium Sativum
Garlic (''Allium sativum'') is a species of bulbous flowering plants in the genus ''Allium''. Its close relatives include the onion, shallot, leek, chives, Allium fistulosum, Welsh onion, and Allium chinense, Chinese onion. Garlic is native to Central Asia, central and south Asia, stretching from the Black Sea through the southern Caucasus, northeastern Iran, and the Hindu Kush; it also grows wild in parts of Southern Europe, Mediterranean Europe. There are two subspecies and hundreds of Cultivar, varieties of garlic. Garlic has been used for thousands of years as a seasoning, culinary ingredient, Traditional medicine, traditional medical remedy; it was known in many ancient civilizations, including the Babylonians, ancient Egypt, Egyptians, Romans, and Chinese, and remains significant in many cuisines and Traditional medicine, folk treatments, especially across the Mediterranean and Asia. Garlic propagates in a variety of climates and conditions and is produced globally; China ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Letters
''Organic Letters'' is a biweekly peer-reviewed scientific journal covering research in organic chemistry. It was established in 1999 and is published by the American Chemical Society. In 2014, the journal moved to a hybrid open access publishing model. The founding editor-in-chief was Amos Smith. The current editor-in-chief is Marisa C. Kozlowski. The journal is abstracted and indexed in: the Science Citation Index Expanded, Scopus, Academic Search Premier, BIOSIS Previews, Chemical Abstracts Service, EMBASE, and MEDLINE MEDLINE (Medical Literature Analysis and Retrieval System Online, or MEDLARS Online) is a bibliographic database of life sciences and biomedical information. It includes bibliographic information for articles from academic journals covering medic .... References External links * American Chemical Society academic journals Biweekly journals Organic chemistry journals Academic journals established in 1999 English-language journals {{chem-journal-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allium Fistulosum
''Allium fistulosum'', the Welsh onion, also commonly called bunching onion, long green onion, Japanese bunching onion, and spring onion, is a species of perennial plant, often considered to be a kind of scallion. The species is very similar in taste and odor to the related common onion, ''Allium cepa'', and hybrids between the two ( tree onions) exist. ''A. fistulosum'', however, does not develop bulbs, and its leaves and scapes are hollow (''fistulosum'' means "hollow"). Larger varieties of ''A. fistulosum'', such as the Japanese ''negi'', resemble the leek, whilst smaller varieties resemble chives. ''A. fistulosum'' can multiply by forming perennial evergreen clumps. It is also grown in a bunch as an ornamental plant. Names The common name "Welsh onion" does not refer to Wales; indeed, the plant is neither indigenous to Wales nor particularly common in Welsh cuisine (the green ''Allium'' common to Wales is the leek, ''A. ampeloprasum'', the national vegetable of Wales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
